<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
		<style type="text/css">
			header{
				height: 240px;
				border: 2px solid green;
			}
			section{
				height: 600px;
				border: 50px outset orange;
			}
			footer{
				height: 120px;
				border: 4px groove red;
				background-color: darkblue;
			}
		</style>
	</head>
	<body>
		<header>
			头部
		</header>
		<section>
			核心内容区
			<a href="#">百度</a>
			<a href="#">新浪</a>
			<a style="font-size: 100px;color: darkkhaki;" href="#">优酷</a>
		</section>
		<footer>
			底部导航
		</footer>
	</body>
</html>
